Connecter for electrical cabinet boxes



April 17, 1934. A. G. VON NORMANN GONNECTER FOR ELECTRICAL CABINET BOXESFiled July 16, 1952 46 GUM M 4. M 0 m 1 m 517 P a 5 A LA m 9 6 m 4 4 m|v m 6 Q 5 u we 15 VI F B 4 l? 1 /77 1 my. a

INVENTOR fl/f/ea M912 lye/mam? c zaal q gggaw Patented Apr. 17, 1934UNITED STATES PATENT OFFICE CONNECTER FOR ELECTRICAL CABINET B'OXES ofWashington Application July 16, 1932, Serial No. 622,872

4. Claims.

This invention relates to improvements in connecters for electricalcabinet-boxes of the form commonly used for the reception of electricswitches, fuses and like electrical apparatus, and the primary object ofthis invention is to provide a connecter for metal cabinet-boxes whichis very cheap and simple in construction; which is easily and quicklyapplied to the cabinet-boxes thus making possible a saving of time;whichis reliable, efficient and durable in operation, and

which serves to mechanically connect and electrically bond two metalcabinet-boxes or like devices together and at the same time affords asmooth conduit between the boxes through which wires may easily andquickly be passed without cabinet-boxes and the washer-like members andspacer together.

Other and more specific objects of the invention will be apparent fromthe following description taken in connection with the accompanyingdrawing. t

In connection with electric wiring it is often desirable to use twometal cabinet-boxes positioned close together, as alongsideof each otheror one above the other, and to connect these two cabinet-boxes with eachother mechanically and electrically by means which will form a conduitthrough which electrical conductors or wires may pass from onecabinet-box to the other. It has heretofore been common practice to useexternally threaded pipe nipples and nuts or internally threadedbushings to connect two cabinetboxes together in this manner. When pipenipples, nuts and threaded bushings are used in this manner the severalparts required for making the connection are more expensive than thepresent invention and require much more time and labor to properlyinstall.

It is therefore a primary object of this invention to cheapen the costof connecters of this na ture and reduce the time and labor required forinstalling the same.

In the accompanying drawing Fig. 1 is an edge elevation of a cabinetconnecter constructed in accordance with my invention the several partsbeing separated a short distance from each other.

Fig. 2 is a side elevation of the same.

Fig. 3 is a sectional view on line 3--3 of Fig. 2 showing the connectercperatively installed in such a manner as to electrically andmechanically g. connect two cabinets and to form a conduit for circuitwires between said two cabinets.

Fig. 4 is a sectional view similar to Fig. 3, except that it is taken ona broken line 4-; of Fig. 3, which is substantially at right angles tothe plane 5 of cross section of Fig. 3.

Like reference numerals designate like parts throughout the severalviews.

In the drawing 5 designates a substantially tubular spacer member verycheaply and easily 7@ formed by bending a strip of sheet metal into theshape of a ring. Two clamping members are provided in connection witheach spaced member 5, each of said clamping members comprising a flatwasher-like plate portion 6 having an open center '7 and having itsinternal edges around said open center curved inwardly as at 8 to fitwithin the end of the spacer member 5. At two or more points around theinside of the clamping members the flat portions 6 of said clampingmembers 89 are widened to form bolt receiving elements 9 which extendinwardly and are perforated as at 10 for the reception of bolts 11 whichextend through the two clamping members 6 and through the inside of thespacer ring 5 and have 5 nuts 12 thereon. The inwardly extending edges 8of the clamp members 6 are bent at slightly more than right angles sothat they will not present any rough edges which insulated wires cancontact when such wires are passed through the 9g connecter.

The type of cabinet-boxes with which this connecter is used are theusual sheet metal cabinetboxes having disc-like stamped sections knownas knock out discs in their walls. In Figs. 3 and 4 I have shownfragments of two cabinet-boxes 13 and 1c of this type as they may appearwhen they are op-eratively connected by this connecter.

The method of applying this connecter to the cabinet-boxes l3 and 14 isfirst to remove the 1 G knock out discs or sections from the cabinetboxes to form holes 15 at the locations where the connection is to bemade, then to place the spacing ring between the two cabinet-boxes inregistration with the holes 15 and to place the clamping members in theinsides of the respective cabinetboxes with the flange portions 8extending through the holes 15 and into the opposite ends of the spacerring 5 thus placing those portions of the metal sides of the boxes whichlie close fTl to the holes 15 between the end of the spacer ring 5 andthe flat portions 6 of the clamping rings. The bolts 11 are theninserted through the perforations 10 and the nuts 12 are tightened onsaid bolts to securely clamp the sides of theboxes 13 and 14 between theends of the spacer ring 5 and the flat portions 6 of the clampingmembers thus securely fastening the two cabinet-boxes together and atthe same time forming an electrical bond between said two cabinet-boxesso that the electrical grounding of either of said cabinet-boxes willground both of said boxes. The connecter also forms a closed conduitwith a smooth interior through which electric circuit Wires may bepassed from one cabinet box .to the other. The projection of the flanges8 through the holes 15 and into the ends of thering 5, pre vents anyrelative sidewise displacement of the several parts.

This connecter is very cheap and simple to manufacture and is Veryquicklyand easily installed in the manner above described, thusmaking-possible a saving in initial cost of manufacture and a saving intime and cost of installation over and aboveother apparatus commonlyused for. this purpose. The bolts used may be of the relatively cheapform ordinarily used in sheet metal work. The connecter may be made invarious sizes to :suit the requirements of the work and the length ofthe spacer ring may be varied to secure any required spacing between twocabinet-boxes. The bolts 11 extend-through the spacer ring in closeproximity to said ring andform'a very eflicient clamping means. The

-- flange portions 8 are deep enough to afford ample strength andstiffness to the clamping members even though the several parts are madeout of comparatively light sheet metal. The edges of the clampingmembers at the locations where the'flanges are bent over are rounded asat 16 so that insulated wires may be easily drawn through the connecterwithout danger of cutting, chafing or damaging the insulation on suchwires. The foregoing description and accompanying drawing clearlydiscloses a preferred embodiment of my invention but it will beunderstood that this disclosure is merely illustrative and that suchchanges in the invention may be made as are fairly. within the scope andspirit of thefol lowing .claims.

"I claim:

1. In a cabinet-box c-onnecter, a spacer member open from end to end,two clamping members.

havingfiat portions of larger over all dimensions than said spacermember, said clamping members having open central portions and havinginwardly extending flanges which project into the ends of said spacermember and bolts connecting said two clamping members and extendingthrough said spacer member.

2. In a cabinet-box connecter, a tubular spacer ring, two clampingmembers positioned at the respective ends of said spacer ring, each ofsaid clamping members having a flat washer-like portion of externaldimensions larger than the internal diameter of said spacer ring, aflange integral with the flat portion of each of said clamping membersand extending into the adjacent end of said spacer ring in closeproximity to the wall of said spacer ring, bolt receiving elements ofgreater width than said fiat portions of said clamping members disposedat intervals around said clamping members, and bolts extending throughsaid spacer ring and through said bolt receiving elements of saidclamping members.

3. In a cabinet-box connecter a tubular spacer ring, two clampingmembers positioned at the respective ends of said spacer ring, each ofsaid clamping members having a flat washer-like portion of externaldimensions larger than the internal. diameter of said clamping ring, theinner edge of each of said clamping members being bent inwardly on asmooth and gradual curve forming a flange which extends into theadjacent end of said spacer ring in close proximity to the wall of saidspacer ring, two diametrically opposite perforated bolt receivingelements of greater width than said fiat portions of said clampingmembers, and bolts extending through said perforated'bolt receivingelements and said spacer ring whereby said clamping members and saidspacer ring may be securely clamped together.

4. In' aconnecter for connecting together two metal cabinet-boxes whichhave holes in the Willlsthereof, a spacer ring of larger diameter thanthe holes interposed between the two cabinet-boxes at the location ofthe holes and holding said two cabinet-boxes in spaced apart relation,two clamping members having flat clamping portions of larger size thanthe interior of the spacer ring disposed'within the respective cabinetboxes,

